Still life With Reptiles

On the road — literally —with researchers charting the new science of road ecology.

It's 4:30 p.m. on a sultry August afternoon when I pull up to a nondescript house in a Sudbury, Ont., neighbourhood. Inside I find my friends Julia Riley and James Baxter-Gilbert, the latter resplendent in a mid-chest hillbilly beard straight out of Duck Dynasty. The last time I'd seen him, tagging along as he radio-tracked turtles on Georgian Bay, he'd been clean-shaven. Clearly it has been a few years. Other than that, little else has changed.

James is busy loading the makings and accoutrements for fish tacos into a cooler. While not quite panic, there is, nevertheless, an air of urgency: he needs to turbo-cobble the meal together because we will leave just after five in order to reach one of the daily survey routes of his latest project by six; and Julia, with an impending application deadline for a scholarship in Australia, wrestles with something on the computer that is causing her considerable grief. I down a proffered tea while they organize.

The house is a classic student affair, with cluttered kitchen, ceiling-high empties, and noisome bathroom. It's also clearly a biologists' lair: in the living room, an aquarium housing fire-bellied toads bubbles beside stacks of nature books and field guides; on the wall, posters of various provincial snake faunas compete for wall space with off-colour science humour downloaded and printed from the Internet. But I don't have time to take it all in before I'm hustled outside and, along with the cooler, assistant Geoff Hughes, and a "crap ton of gear," wedge into a tiny Laurentian University car whose grill appears purposely spray-painted with layers of insect carcasses. The irony of this will become apparent.

A flashing rooftop light and sign announcing "CAUTION: Vehicle makes frequent stops" define this field vehicle deluxe. It smells like one, too — a fetid mix of soiled clothing and organic decomposition (also ironic), with the unmistakable pong of snake shit thrown in for good measure. On the dashboard, braced against the windshield behind a plastic alligator mascot, sits a metre-long set of tongs for handling rattlesnakes. Headlamps dangle from the rearview. Elsewhere are notebooks, safety vests, telemetry equipment for tracking radio-tagged snakes, scanners, bags, bins, gloves, thermometers, various tools for measuring animals, and gear for collecting blood samples. My first thought: for a young science, road ecology is pretty gear-heavy.

At fewer than 20 years old, road ecology is, by definition, an emerging discipline — albeit one that should have been birthed much earlier. After all, we've been messing up wildlife populations with roads and other transportation corridors for centuries, drawing lines on the landscape that carve up habitat and territories, deliver air and water pollution, impede seasonal movements, and interrupt gene flow. Not to mention the critical impacts of direct mortality to everything from pollinating insects to large mammals. For humans, roads get us where we want to go; for other animals, they're often the most dangerous element in their environment — a one-way ticket to oblivion. No more so than for reptiles.

Already one of the most globally imperiled animal groups, roads not only present the hazard of perilous crossing to these small, slow-moving creatures, but boast features that attract species with certain life-history and behavioural traits to the danger zone: snakes naively bask on asphalt to absorb radiant heat; turtles find sandy shoulders perfect for nesting. We converse on these pitfalls as we drive, backgrounding the work we're about to undertake as part of James's study of reptile road mortality along a newly expanded section of Highway 69/400 in central Ontario. This major thoroughfare — one of several links to near-north cottage country from southern metropolises like Hamilton and Toronto — bisects the labyrinthine coastline of Georgian Bay, home to Canada's richest reptile biodiversity, its presence contributing to the large number of these that are designated Species at Risk (SAR). Already big and busy, the highway's expansion involves twinning, with the associated increase in traffic expected to present long-term significant threats to the region's six turtle (five of which are SAR) and 12 snake species (five of which are SAR).

Conducted over two years at a pair of sites located 50 km apart, 2013 was the concluding summer of James's investigation, at the end of which he would have abundant data from an unmitigated southern control site on the Magnetawan First Nation, where roadwork had yet to commence, and from what he labelled the "impact site" — a section of highway that, in 2012, was a two-lane with no mitigation for crossing reptiles, but by summer 2013 had transformed into a four-lane. At the impact site, traffic streams were now separated by a wide, intervening meridian and mitigation structures that included stretches of mammal and reptile fencing, as well as five ecopassages: four under the road for small critters, and an overpass for larger mammals. Each section, 13 km in length, was driven by crews in both directions three times a day — 9 a.m., 6 p.m. and 10 p.m. — corresponding with known periods of reptile movement. James looked to observe changes to the abundance of reptiles on mitigated versus unmitigated roads, along with other aspects of the efficacy and utilization of the mitigation itself.

About 40 km south of Sudbury we reach the impact route, marked by a line spray-painted on the shoulder. Pulling over, we await the start of the 6 p.m. cruise, simultaneously undertaken by a different crew at the Magnetawan control site 50 km south. Timing our respective starts by text (phones being the world's greatest cluster-management tool), we drive only 100 metres before finding the first victim: a freshly killed eastern gartersnake. The crew springs into action and I have a chance to see what they've done three times a day, every day over the past two summers: they take road and air temperatures, employ a scanner to see if this animal was one they'd previously inserted a passive integrated transponder (PIT tag) into, then measure and sex the unfortunate snake, making a blood smear for later genetic analysis. These last three, I learn, are not always possible; many animals are nothing but fragments when found. Sometimes only molecules.

After driving the section the other way and finding little — despite stops for potential kill signs on the pavement — we head south to Magnetawan. James's southern staging area is a grungy trailer parked beside a house owned by Debbie, an amiable Magnetawan who worked briefly for James the previous summer before cranking her ankle on a slippery log and deciding fieldwork wasn't for her. But she likes the project and agreed to help out with a place for his crew to park their trailer. She even lets them use her bathroom for showers.

After a delicious dinner of catfish tacos with black-bean-and-corn salsa and chunky cilantro-infused guacamole, James and I leave Geoff and Julia to deal with the southern route and head north for the 10 p.m. survey with two other crew in tow — Liv and Jimmy's younger sister, Jen who also worked on the project last year and readily picked up the skills needed to train this year's crop of assistants. Liv is a bat biologist working on an agricultural project out of Carlton University that looks at how to arrange a farm's land mosaic (fields, forest, ponds and crops) so as to maximize the help nature gives to the operation and vice versa.

Slowing down to cruise the dark road section, we immediately find a watersnake hit since we were here four hours ago. It's large — over 80 cm long — but already run over so many times it's difficult to measure. It only takes minutes and a few trucks on hot pavement, says James, to produce "snake jerky" — one of a constant stream of black-humour roadkill euphemisms (are there any other kind?) that deliver a level of morbidity that takes getting used to and includes "crispy critter," "frog leather," "peelers" (where skin has been rolled off an animal into a little ball), "tissue tumbleweed" and "bananaconda" (an actual phenomenon — banana peels tossed from vehicles with frequent abandon resemble squashed snakes, fooling crews into stopping).

Some highways have dedicated crews that clear visible roadkill away as fast as it accumulates; others rely on maintenance workers to remove hazardous large mammal carcasses. But I'm rolling with a crew that scours pavement with combs fine-toothed enough to sieve even the tiniest mangled creature. Though it's apparent they're inured in some sense, they feel no better about the death of threatened and endangered species than I. While scraping up bits of turtle carapace — a structure evolved over hundreds of millions of years for defensive purposes but no match for a car, scattering along the asphalt like shards of boney pottery — they display a sanguine shell of their own, momentarily adopted to get the work done. Me, not so much. When I see my first-ever Massasauga rattlesnake, a smeared mass of skin and skeleton and entrails, barely recognizable save for small patches of spotted skin and the distinctive longitudinal cheek stripes that define this comely species, it makes my heart sink. But this visceral reaction to a single, needlessly killed individual isn't just because it's a SAR. Had I seen one of these magnificent creatures in the wild as a kid it would have been one of the most memorable moments of my life. But these guys see up to a dozen a day. All dead.

"You get used to it," says Julia, "but there are still moments when it gets to you. Like when it's an older animal, or a female turtle with eggs or a big snake with live young inside her, or an animal that you've marked or have been tracking."

That would hit home again for Julia the next morning when she'd come across a DOR turtle she'd radio-tracked for months. Part of the study involved marking live animals encountered on roads with PIT tags to see if they turned up again — alive or dead. They were also radio-tracking a select few turtles and rattlesnakes to chart behaviour around roadways, checking whether they crossed them as part of seasonal movement and if so, how many times. Through this process you got to know the animals and, one imagines, they got to know you. And then one day there they were, as flat as your spirit when you discovered them.

Although it's an obvious part of it, road ecology isn't only about death. Look into the science and all sorts of interesting data appear to inform our understanding of behaviour and adaptation (not that making animals run traffic gauntlets is a good way to conduct experiments). For instance, with an estimated 80 million birds killed on U.S. roads each year, and millions more in Europe and elsewhere, losses to vehicles are a serious problem for which changes in roadway design and maintenance have been proposed. With such magnitude of mortality often focused on particular species, scientists might expect natural selection to favour individuals that either learn to avoid cars or are less likely to collide with them due to some inherent trait; if so, roadkill frequency should decline over time in these species. Such baseline information, however, was scarce until Charles and Mary Brown of the University of Tulsa in Oklahoma noticed something interesting during their 30-year study of social behaviour and coloniality of cliff swallows in southwestern Nebraska. The birds usually attach their mud nests to cliffs but find manmade structures like bridges to their liking as well. Following the birds' occupancy of such roadside nesting sites, the Brown's found the frequency of roadkilled swallows declined sharply over the next 30 years, and that DOR birds tended to have longer wings than the population at large. The conclusion was inescapable: the traffic hazard was selecting for individuals with shorter wings and thus, greater maneuverability in avoiding collisions. Such fast-tracked adaptation is possible only where populations are large to begin with, where reproductive rate is high enough, and where there is a reasonable chance of driving a trait — like wing length — in a direction that benefits the population before it's wiped out. In other words, OK for swallows, but a turtle that might be more fleet-footed than another is still just as likely to get flattened on a road. And locally, don't expect Pemberton's threatened snakes to outrun the bumper-to-bumper pickup truck traffic on Mackenzie Ridge anytime soon. But that's where ecopassages come in.

The advent of a new science aimed at a problematic milieu means new partnerships and new opportunities for solutions. XING, which aims to (re)connect landscapes, is a partnership of the Toronto Zoo, the Ecological Design Lab at Toronto's Ryerson University, and ARC Solutions, and its public outreach display at the zoo explains just why roads are so bad for critters. To begin, wildlife with large home ranges travel long distances between food, mating and overwintering areas, and the bigger an animal's range the more likely it is to encounter roads: the average grizzly bear range is 1,000 to 2,000 sq. km., cougar 130 to 400 sq. km., moose 5 to 40 sq. km. No surprise then that some four to eight large animal collisions take place in Canada every hour. National averages for the cost of these collisions are $6,617 per deer, $17,483 per elk, and $30,760 per moose. Beyond the obvious economic and safety issues, the effort to reconnect habitats asks a simple question: how do we carry a landscape over a road? The answer is to make wildlife crossings visible, with a harmonious aesthetic, visually re-establishing our own relationship to the landscape of nature — while providing safe passage and also making motorists aware of the habitats they're fragmenting. And while it might take animals a while to get used to them, crossing structures work, as exemplified by the substantial win in Banff National Park.

With the average time between vehicles on the Trans-Canada Highway through Banff National Park hovering around three seconds, by the 1990s it had become a virtual bowling alley with wildlife as the pins and vehicles the balls. But continuous fencing and more than 30 crossing structures installed along the highway have now yielded 15 years of research on their utility: using fur samples, images from remote cameras, and tracks, 200,000-plus mammals have been detected using crossing structures, with a concomitant 95-per-cent reduction in wildlife collisions on the road.

Next morning James and I drop the women off at a wetland where they'll spend the day trying to catch painted turtles for a behavioural study James is conducting around the willingness of these creature to use mitigation culverts. He and I drive the impact route and find only a dead watersnake. We then park to do a daily fine-grained search in which a 4 km (2 km in either direction) chunk of the route is walked. This is particularly illuminating, since the view from a car is analogous to an aerial survey, while a ground search yields far more. Within minutes we find the barely visible remains of gartersnakes and watersnakes we'd missed from the car. Halfway in lies a twitching smooth greensnake that wasn't there when we passed by minutes ago; with their preternatural colour, a mortally wounded greensnake is small and sad, especially since they quickly turn blue because xanthins (yellow pigment) break down faster than cyanins (blue pigment) after death.

One of the more illuminating aspects has nothing to do with animals dispatched on the highway and everything to do with the private lives and practises of the dispatchers. Items found by the road include numerous plastic juice bottles filled with pee (a trucker trick?), dental picks (many people seem to clean their teeth while driving), and disposable diapers, whose lobbers deserve a special place in eco-hell. More disconcerting are boatloads of empty liquor and beer containers, which, along with falling asleep at the wheel in such remote, unlit areas, might explain the disturbing preponderance and evidence of horrible car accidents: as we walk, it's clear where vehicles have gone off the road into reeds and swamps and forests and lakes; where they've suddenly and tragically shot across lanes to plow head-on into rock cuts, leaving shards of windshield and the kaleidoscopic debris of turn signals, rubber strips, chrome bumpers, metal, fiberglass, hubcaps and tires. Some of these accidents clearly weren't survivable, others no more than a surprise to the occupants who suddenly found themselves sitting in a swamp. What it adds up to in terms of road ecology, however, is this: the effect of inattention. People driving at high speed on this road are barely aware of what they're doing let alone what's outside their vehicle. Cautioning folks to slow down or watch for snakes and turtles by posting signs in such an area is likely to have no effect, though this isn't true where speeds are lower — as in parks — where reduced mortality has been seen on signed roads. It also doesn't help a snake's cause that an admitted three per cent of drivers will purposely run over them.

Equipped with small Ziplocs, we're also picking up dead bugs for a companion study, considerably slowing the enterprise. The bugs appear in waves in various parts of the route and vary from day to day depending on weather — bumblebees, dragonflies, beetles, and plenty of endangered monarch butterflies. (Over two summers, James will collect 117,000 road-killed insects and publish a paper on the astronomical number of insects killed on roads. Their estimate of insect mortality on Highway 400 — a medium-use road of 10,000 vehicles per day in an area of medium insect diversity — was extrapolated to the entire length of similar roads in Canada and the continental U.S., to yield figures of 10 billion butterflies and moths, 25 billion bees and wasps, and a staggering 60 to 190 billion flies dying per year.)

On the way back to the car I have the gratification of saving a small painted turtle peering out from the shadow of a guardrail post — basically right above an ecopassage designed to funnel them under the highway; but the meridian is flooded and the plastic reptile fence — clipped to a metal fence with links large enough for the turtle to walk through — is now below water level, completely ineffective. In fact, the mitigation measures constructed by the Ontario Ministry of Transportation to reduce reptile road mortality and provide safe crossing options will, in the end, engender the opposite. "Basically, the fence failed," James will tell me, "which resulted not only in the animals not being protected, but also correlated with an increase in post-mitigation death rates. In other words, whatever they were doing to get around the fence actually seemed to increase the likelihood that a reptile on the road would be dead — 20-per-cent higher for turtles and a 25-per-cent rise for snakes. So this type of fencing is no good, it's not installed correctly and is prone to washouts, rips, and bursts. That being said, we're all learning something here, and even the people installing these fences are on the right track."

As it turned out, of 996 reptiles encountered on the road over two summers, 83 per cent were DOR and included a wide assortment of species — including SAR Blanding's turtles and Massasaugas, notable for their low status and high numbers. "As for words of wisdom," James summarized, "people need to understand that mitigating for human safety is different than mitigating for conservation. A fence can keep deer and moose off roads, but their populations are so large and spread out that there's a much lower risk of fragmentation to populations. Reptiles are different. They're small and damned determined, which means that they'll walk around an incomplete fence, climb over it, find every flaw along its length, whether damage from vegetation, fallen trees, flooding, or poor construction. So the traditional method of putting up some rinky-dink, knee-high, plastic or hardware cloth fence isn't good enough. These require constant upkeep, something that's too costly to do on large expanses of open highway at this latitude in this climate. We need to build something that will last longer and won't require daily patrols, weekly patching or yearly replacing."

But if mitigation wasn't necessarily an improvement for a variety of reasons, could it have been? Yes — if built into the highway plan rather than added post-hoc as is typically undertaken. "You aren't allowed to build a shitty highway because it will kill people," says James, "but you're allowed to build a shitty wildlife fence because no one in government really cares. But if you're forced to incorporate and build that fence as part of highway design, it's bound to be of higher quality."

In the end, everyone knows we can't stop roads. We can't stop cars. And we can't stop people travelling or going to their cottages (ironically, supposed wild sanctuaries). But we can do better. And the work of road ecology is pointing in the direction that effort should take. As James puts it: "If road ecology has taught me anything it's that simply understanding a problem doesn't do squat: you have to want to fix it — and in the best way possible."